Summary:  Rose McCarthy

Editor:  Jane Standen

 

With Dr Jane Standen, Consultant Anaesthetist and Interventional Pain Specialist, Sydney, Australia 

 

James talks to Dr Jane Standen about chronic post-surgical pain.

Jane is s Consultant Anaesthetist and interventional Pain Specialist.  She studied medicine at the University of Sydney and trained in anaesthesia at the Prince of Wales Hospital, Sydney.  Subspecialty training in pain management was undertaken at the Michael J Cousins Pain Management and Research Centre at Royal North Shore Hospital.

Jane has expertise in the treatment of both early onset and persistent pain.  She specialises in minimally invasive procedures, aiming to reduce pain and enhance quality of life.  She practices with an empathetic manner and takes an evidence-based approach.

Jane is an honorary tutor with the University of Sydney Masters in Pain Management and is actively involved in pain management education at the Mater Hospital and Royal North Shore Hospital.  She regularly conducts GP educational sessions.

She is appointed at Norwest Private Hospital, the Sydney Adventist Hospital, the Mater Hospital and Royal North Shore Hospital.

 

 

Introduction

  • By definition, chronic post-surgical pain is new pain post-surgery that persists outside the time of normal wound healing. The definition is currently changing according to the International Classification of Disease 11 to ”persistent pain continuing at 3 months post-surgery or significant tissue trauma”. Managing chronic post-surgical pain can be challenging and may require close management by a multidisciplinary team.

 

Case – You are asked to see a gentleman on the wards who is waiting for pleurodesis for recurrent pneumothoraces.  He has a background of depression and is very apprehensive about the procedure,  He has 6/10 pain and is distressed wanting the procedure done now saying “dying of pain”.

 

1. Initial approach

  • Challenging patient for a junior doctor - in this type of patient, it is difficult to determine how much pain is due to pain generators and how much is attributed to distress
  • Do not engage in the patient's distress - remain calm
    • An empathetic approach will be the easiest way to manage the situation
    • Take their issues seriously and validate their concerns
  • Seek senior support if you feel the situation will escalate
  • Consider erring on the side of caution if the patient is waiting for surgery
    • Provide analgesia appropriate to what the patient is describing
  • Consider that the patient may be apprehensive of aspects of the procedure
    • For example, the general anaesthetic - it may be appropriate for the anaesthetic registrar to come and talk to the patient
  • If the patient has a significant history of a mental health problem, it should be optimised before the patient has surgery
    • Determine if they take anti-depressant/ anti-psychotic medications
    • Determine if there is suicidality risk
    • Consider if a mental health officer needs to be involved

2. How do we reduce the risk of chronic post-surgical pain occurring? Why does it matter?

  • Chronic post-surgical pain matters because persistent pain can interfere with a patient's ability to function which has both societal and vocational considerations
  • Reducing the risk of chronic post-surgical pain involves:
    • Pre-operative
      • Assess the patient
      • Perform psychometric scoring
        • For example, levels of anxiety, depression, pre-operative catastrophisation - with higher scores reflecting greater incidence of post-operative chronic surgical pain
        • Consider if psychometric factors can be modified - however this is difficult if the patient is in hospital and due for surgery within 24 hours
    • Other factors for higher risk of chronic post-surgical pain: younger patients, female patients and patients with history of chronic pain
    • Intra-operative
      • Higher risk for certain procedures, for example thoracotomy, mastectomy, inguinal hernia repairs
      • Surgical minimisation of intra-operative nerve lesioning
        • However, fine anterior cutaneous nerves will inevitably be cut in thoracotomy and mastectomy operations when an incision is made
    • Post-operative
      • Less severe pain post-operation indicates less risk of developing chronic post-surgical pain
      • Specific techniques
        • For example, thoracic epidurals for thoracotomies, para-vertebral blocks for mastectomies
      • Currently awaiting results of the ROCKet Study (a randomised control trial)
        • Utilises a ketamine protocol to manage post-operative pain
        • Involves giving a bolus ketamine dose intra-operatively then continuing a post-operatively infusion for 72 hours
        • May alter how we give anaesthetics and provide analgesia post-operatively

3. The operation goes smoothly and three days later the patient is due for discharge with oxycodone and regular paracetamol. He will see a local GP for follow up. Should patients with acute surgical pain be discharged with medications such as oxycodone?

  • It is common practice to discharge a patient with a definitive amount of short-acting opioid
  • Encourage provision of a non-pure μ-agonist
    • For example, tramadol immediate release or tapentadol immediate release
      • Rather than a pure μ-agonist, for example, oxycodone
      • Both tramadol and tapentadol are associated with lower rates of abuse in the community
  • Provision of analgesia should be limited in the opioid family
    • Follow up with GP in three days is recommended
  • If there is any history of opioid misuse or suggestion of opioid diversion, the patient should not be given opioids for discharge and alternative provisions be made

4. The patient is booked into the cardiothoracic clinic 10 weeks later. The are no further pneumothoraces but he has been experiencing ongoing pain since the operation. He describes a deep, burning sensation across the chest. He is unable to go back to work because of the pain. What else would you consider in your pain history?

  • In order to make a diagnosis of chronic post-surgical pain it is important to exclude:
    • A contributing factor to the pain - for example, infection, inter-current medical problems (example, malignancy)
    • Determine if the pain is different to the pain they had pre-operatively
      • By definition, chronic post-surgical pain needs to be a new type of pain
  • Determine if the pain is neuropathic (burning, stinging, freezing cold, pins and needles) or nociceptive (aching)
  • Examine the patient: determine if there is altered sensation around the surgical site (increased or reduced sensation), this would make the diagnosis of chronic post-surgical pain more likely

5. For a diagnosis of chronic post-surgical pain, should you order blood tests or imaging?

  • Chronic post-surgical pain is a clinical diagnosis
  • If there is an inter-current issue that you suspect is contributing to the patient's pain then that should be formally investigated
    • For example, inflammatory markers for suspected infection; imaging for suspected compressed nerve root / plexopathy

6. In clinic, what advice do you give to a patient with chronic post-surgical pain?

  • Explain to the patient they are in the early days post-surgery
    • Progress is unclear but appropriate management will be aggressive at this stage
    • Early referral to a multi-disciplinary pain clinic in order to reduce the incidence of chronic post-surgical pain
  • Multi-disciplinary pain clinics address the psychological, pharmacological and physical therapies to treat this patient's plan

7. When a patient presents to the Emergency Department with post-surgical pain, it is important to look for underlying complications. Should junior doctors be doing blood tests and imaging or should we be doing more on history and re-identifying what is probably chronic post-surgical pain?

  • Good communication between specialty teams is important to minimise unnecessary investigations that are performed
  • Close collaboration with the surgical team and pain management service will help reduce unnecessary tests
  • It is always important to rule out possible contributors like infection, but once it is ruled out it is not necessary to contribute investigations for more obscure possible contributors

8. What treatment options are now available for chronic post-surgical pain?

  • Multidisciplinary team care:
    • Physical therapy
      • To ensure the patient remains active and functional
      • If the patient has not gone back to work that should be addressed
    • Psychological therapy
      • To find factors pertaining to the pain
      • Could the patient's mood be modified to improve the pain through cognitive behavioural therapy or anti-depressant treatment?
    • Pharmacological therapy
      • If there is neuropathic pain the patient may benefit from a small dose anti-depressant or gabapentinoid (pregabalin or gabapentin)
  • Encourage de-escalation of opioid analgesia, with replacement of a pure μ-agonist such as oxycodone to a less pure agonist such as tapentadol or tramadol

Take home messages

  • Chronic post-surgical pain requires close collaborative communication between all treating specialty teams, including the surgeons, the pain management team and Emergency Department
  • Opioid escalation is not appropriate treatment for chronic post-surgical pain
  • If the patient has a possible neuropathic pain then anti-neuropathic agents may be appropriate to trial along with a non-pure μ-agonist for analgesia such as tramadol or tapentadol to facilitate activity

If you enjoyed listening to this week’s podcast feel free to let us know what you think by posting your comments or suggestions in the comments box below.

 

 

Podcast

Chronic post-surgical pain